1. Field of the Invention
This invention relates to a method and an apparatus for cleaning metal articles, an apparatus for rinsing metal articles and an apparatus for removing water from metal articles.
2. Description of the Related Art
Since an easily corrosive metal such as bearing steel begins to rust as soon as it is soaked in water, it has hitherto been extremely difficult to clean parts, semi-assemblies or products made of such metal (hereinafter referred to as "metal articles"), particularly precision metal articles including bearings.
Conventionally, metal articles have been washed in alkaline washing water and then rinsed in rinsing water to which a rust inhibiter had been added so that they do not rust. Thereafter, they have been dried by an air knife or a hot-air dryer.
Using this conventional method, however, there is a problem in that a residue of a rust inhibiter remains on the surfaces of metal articles. When rinsing water is disposed of as waste water, this requires that a waste-water treatment device be provided, thereby increasing the cost of cleaning the metal articles. Further, after removal of rinsing water from the surfaces of the metal articles, stains are likely to remain on their surfaces, due to use of the rinsing water containing the rust inhibiter.
Fluorocarbon or 1, 1, 1-trichloroethane has been used to improve the drying quality of the metal articles after removal of the rinsing water. However, both materials destroy the ozone layer, causing natural environmental disruption. In addition, the latter material is apt to damage the operator's health.
There has been further developed means for rinsing metal articles in deoxidized rinsing water. Using this means, however, the appearance of stains and small rust spots could not be prevented, because the conventional rinsing-water removing method and drying method were used.